1. Field
One embodiment of the invention relates to a circuit board, such as a flexible printed circuit board or rigid printed circuit board, a connector connectable to the circuit board, and an electronic device with the circuit board and connector.
2. Description of the Related Art
In accordance with the development of downsizing and high integration of electronic devices, the electronic units incorporated in the electronic devices are also reduced in size. Similarly, reduction in size and pitch, high integration and high accuracy are required of flexible printed circuit (FPC) boards for connecting the electronic units, and connectors (FPC connectors) connected to the FPCs.
For instance, to appropriately mount an FPC on an FPC connector, their outlines are processed for positioning. Outline processing is often performed on the opposite ends of the FPC (the opposite ends that are brought into contact with the insertion hole of the FPC connector when the FPC is inserted therein). In this case, the outlines of the opposite ends must be processed highly accurately so as to prevent contact failure from occurring at the opposite ends.
Jpn. Pat. Appln. KOKAI Publication No. 2003-317830 (see, for example, FIG. 8) discloses a structure in which two boards have respective projecting contact portions, through which the wiring patterns of the boards are coupled to each other.
In general, the outline processing of the opposite ends of an FPC is performed after wiring is formed on the FPC, and may well cause errors. Even a slight error may cause the contact position to be greatly deviated from the correct position on a highly integrated narrow-pitch FPC wiring pattern, thereby causing electrical contact failure. This may occur in rigid printed circuit boards, as well as in FPCs.
Further, in the above-mentioned structure in which two boards have respective projecting contact portions, through which their wiring patterns are coupled to each other, electrical contact failure may easily occur because of the influence of dust or adhesive, etc. When a clearance is defined between the boards, contact failure may also easily occur.